I have been asked to prepare questionaire for interviewing new applicants for an electrician job.

I would like your help in determining suitable questions, keeping in mind that the interviewee is under stress, confused and under the microscope. May not be able to answer with cool mind as in normal case when programming or troubleshooting.

What would be the general question, that will bring out the basic info necessary to judge him, knowing that question should be basic to any plc, we may be using Siemens, and he may be very proficient with AB. Now if we ask him questions related about Siemens it won't bring out the Best in him.
What we want to know is how proficient he is with programming.
Can you help me phrase the questions which will be able to get the best out of him.

For e.g., will the follwing be good to ask?
1. Do you know about direct/indirect addressing, have you ever used it for programming or troubleshooting?
2. If yes, what is its strong/weak point?
3. What programming language do you use? Ladder, Flowchart or STL?

These are the general questions I have thought of, can you please help me generate some better ones, to select the right candidate.

I would ask about how he generaly structures or organizes his programs.

If he has benn structuring the works he does he must have a way. It could be his way but what is relevant is that he has a structure. The next guy will appreciate it.

Also I would ask if he generaly does programs from scratch or does he usually work on stuff others have done before. There is a big difference between one that can start from zero and one that modify existing programs.

your hiring an electrician to program plc's? i dont want to pick on job titles,,but this reminds me of a local company here who were looking for 'trainable' maintenance guys and gave them a test on some fairly indepth plc stuff and couldnt find anybody to hire(especially for the pay offered),,

Fred Raud

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Some people would ask those questions. Some wouldn't.

I like to give someone a list of 10 inputs, six outputs, some sequence of events info, and have them write a program.

I once had a portion of a plant with over 300 plc's, and a good portion of them were a combination of drum and ladder logic. Most people from the outside world didn't have a clue.

As far as electricians writing programs, this is increasingly more common. With more downsizing, less engineers.

I was given an omron last year, with a switch, light, power supply, and some wire. It was preprogrammed, just wire it up. It was also "backwards" logic. (Ground to turn on the input, output normally high, grounds for "ON" state). I got it right, along with two others. 17 were given 3 three tries and failed.

Saw an ad for a company in Illinois Saturday, and the desription included CNC setup, CNC programming, CNC operating, PLC programming, facility maintenance (READ janitor), and outside maintenance (READ snow and grass removal).

I liked the question, "What was your greatest challenge, and how did you overcome it?". I had this twice early last year, and several others here mentioned it also. Maybe the HR people figured out how lame it was!!!

Why not print out some logic from one of your programs, and have them explain what is happenning?

Originally posted by CaseyK:Why not print out some logic from one of your programs, and have them explain what is happenning?

Good one. That is probably more typical of what they will be doing on a daily basis if they are doing machine maintenance or testing.

That is, unless you really do plan on locking them in a room with a computer, a case of Mountain Dew and 10 candy bars and wait for code to come out the mail slot. Then the test needs to be a little more in depth.

I think your approach is a bit bass-ackward.
Ask the guy about what he's done, describe some job/project he's worked on. Once you get him started, you can work in your various questions as part of the conversation. Hopefully, you can keep your probing in context.

Location: In the cornfields, on the prarie, outside Chi-Town, a few miles beyond the boondocks.

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Quote:

Originally Posted by kamenges

Good one. That is probably more typical of what they will be doing on a daily basis if they are doing machine maintenance or testing. Keith

I didn't think I had a good understanding of circuitry and troubleshooting when I was young. I had been designing cookie cutter control panels and switchgear for CAT engines and generator sets. Mostly redrawing the same thing over and over, add a light or an alarm, maybe an oil pressure timing circuit, or something. 95% of the orders were basic stuph, and the 5% that I worked on were nothing like they have today. None of the really fancy stuph like BobB and others play with.

I went and interviewed for an electricians job, after a year on the drawing board. After a few minutes of chit chat (my father had built the guys house, my grandmother once lived next door to him, he had two daughters...err, nevermind), anyway, he pulls out a large machine schematic. Starts asking questons.

When this light is on, and the motor doesn't run, WHY?

Motor runs, this light isn't on, what's wrong?

Push this button, everything goes off, what could be wrong?

After a half hour of this, I felt pretty confident about my abilities. Never went to work there, they had 1300 people then, (1973), and today are down to 135. And they are closing this year. Oh well, I had more fun elsewhere, and a lot cleaner environment, TOO!

I always like it when you get a shop tour! sometimes they will ask questions when you are doe, what you saw that could be changed. Sometimes it is a test. A few times, they were after free advice, and there was no job. Oh well.

Asking what someone has done is a good idea. Then, asking "How
did you do it".

, keeping in mind that the interviewee is under stress, confused and under the microscope. May not be able to answer with cool mind as in normal case when programming or troubleshooting.

ali

Exactly when you want to hit them!! You WANT to see what they do under stress..When the line is down and people (White Hats) are standing over him watching..do you think he might get a little stressed when he is troubleshooting?

I find you can tell more from a guy under stress than any other time..Hit them with some tough questions..it dosnt matter if he gets them right..just see wich way his mind takes the problem...

Ive been on both sides of the table. For what its worth... here, Dont ask vague questions. Try to see if the person is trainable and open to new ideas. Can they accept change. Do they have a good safety record. Is a challenge going to fustrate or motovate them. Take them to a computer and make a simple hands on test for them. Copy a file to a directory. Make a directory. Type a paragraph in a word processor (notepad) and save it. Edit a simple rung in a PLC. After this ask yourself if their claims are what you see in basic computer skills. This isnt perfect, but it is better than asking trouble-shooting questions that have many answers, some good and some meaningless. The chargehand/leadhand should be there, the maintenance supervisor, never more than 6 people total. The complete interview should be no more than 20 minutes max. Use the people at the interview by asking their first impressions. Write a letter to all interviewed and answer their questions if they have any about the interview. Be polite, and on time. There is my two cents....

I wrote a test where I used to work that craftsman applicants were required to take. There were electrical symbols, generak questions, (what is an RTD used for?), and questions about the function of a simple control scheme where the hardwired and plc programs were provided.

NOBODY aced this test. The average score of all applicants was about 60%. It was hard. That's the way we wanted it. We told the applicants that they weren't supposed to ace it.

The point is that if everybody does well on an easy set of questions, you have no ruler in which to measure and compare the knowledge of applicants.

Mix the questions so you get an idea of basic knowledge about electricity as well as more advanced knowledge about control. But make it hard.

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Quote:

Originally Posted by john paley

NOBODY aced this test. The average score of all applicants was about 60%. It was hard. That's the way we wanted it. We told the applicants that they weren't supposed to ace it.

That might be a good approach. Perhaps with the addition of Post Office Scoring, number of right minus number of wrong. A high score means a very good apptitude. A lower score might not rule someone out, that if they weren't 110% sure, they might get more info then going into it blind.

The RTD question is good. After twenty years of controls, switchger, and general engineering, along with maintenance work, I stumbled across my first RTD at GE. None of the engineers there could give me a real clear understanding. Just that it was in the auto-transformers, most were bad, and you had a heck of a time checking it with a vom.

I have aced a lot of the tests at some plants. I also felt that they probably had little to do with anything that went on in the plant. I also see a lot of test with transistor questions. I haven't seen a lot of industrial sparky's, or plc techs, pulling a transistor out and replacing it. This may be a regional thing, just not done around here. I did for a long period of time in Peoria, but the electricians and the electronics techs were two seperate departments, different buildings, and two completely different divisions. The seven electricians that I had in my area of the tire plant, only three would have had the ambition to pull a transistor, and maybe two could have done it successfully.

I do not think that a mail order test is a good idea.

If you have 240 open delta wiring, make sure they understand the wild leg. I have seen a lot of old timers not get it. Along with the difference between wye-delta. Some plants have 480 wye in some areas, and 3 wire delta, with one phase grounded. A lot of strange problems arise there.

Back to the original problem.

If they understand plc's really well, they can probably pick up the different styles of programming. Do you guys have any training package for your particular software, or does your distributor have any classes for them?

You can hit him with a question that you know he doesn't know and see his reaction. You can tell alot about people when this happens just from their response. You can determine what his proceedure is for finding the answer. The fact is it is impossible to know everything but it is important to have the resources to figure out the problem. Ask him what he would do to figure out the problem.

The best interview I ever had. This is from the applicant stand point. I went through the normal battery of questions with HR and the 20 something engineer. This was about 10 minutes of the normal B.S. questions and the same type of answers. Then in came an old just out of a greasy machine supervisor. He had 3 papers. An old schematic, A ladder diagram and a hydrolic diagram. The schematic was so old alot of the symbols I had never seen, the ladder had some obviouos mistakes, and the hydrolic was way above my head. He put them in a pile in front of me. He had me take a few minutes to look them over and then asked a series of questions about each. He told me later some things he expected me to know and others he knew I would not but just wanted to see how I reacted. He said he had been doing the same interview with the same schematics since 1978. I got through the interview. Went home and search for answers to some of the thing. I did not know and the next day got an offer. Wasn't there long (plant moved) but I learned alot.

Good one. That is probably more typical of what they will be doing on a daily basis if they are doing machine maintenance or testing.

We're hiring for maintenance right now, and I've been giving them a motor start/stop circuit implemented in ladder. I've been suprised at what a good indicator it is. Some of the guys that claim no PLC experience mention it looks like a hard wired start /stop circuit. Some try to trace it, which I take as a good sign. Some pick it out for what it is and the rest just stare blankly and then make up excuses or admit that they really don't know despite listing 'PLC experience' on their resume.

Either way it's a simple test that gave me a pretty good idea of what the guy knows without completely overwhelming them.